Related Experiment Video
Updated: Jul 10, 2026

Larval RNA Interference in Silkworm Bombyx mori through Chitosan/dsRNA Nanoparticle Delivery
Published on: October 4, 2024
Differential regulation of ecdysteroidogenic P450 gene expression in the silkworm, Bombyx mori
Naoki Yamanaka1, Naoko Honda, Noe Osato
1Department of Integrated Biosciences, Graduate School of Frontier Sciences, The University of Tokyo, Japan.
Abstract:
The regulatory mechanisms of ecdysteroidogenic P450 gene expression were investigated in the silkworm, Bombyx mori. Bommo-FMRFamide (BRFa), a neural suppressor of prothoracic gland (PG) activity, was found to suppress the expression of several P450 genes induced by prothoracicotropic hormone (PTTH) in the PG. A transcription inhibitor suppressed PTTH-induced expression of the P450 genes and the opposing effects of BRFa, while their short-term effects on ecdysteroidogenesis remained unchanged. This result suggests that the effects of these factors on the P450 gene transcripts become obvious on a longer time scale. Moreover, spontaneous expression of a P450 gene was observed in long-term PG culture, and was repressed by juvenile hormone. These results explain well the developmental fluctuation patterns of the P450 gene transcripts in the PG, indicating that multiple factors coordinate to regulate basal PG activity during insect development.
More Related Videos
Related Concept Videos
Dosage Compensation
In addition to sexual development, the X chromosome has genes involved in autosomal functions such as brain development and the immune system. Therefore, males and females with distinct numbers of X chromosomes will have...
Master Transcription Regulators
The Ratio of X Chromosome to Autosomes
Normal male Drosophila has a ratio of one X chromosome to two sets of autosomes. In contrast, normal female Drosophila...
Cell Specific Gene Expression
Position-effect Variegation
Background and Environment Affect Phenotype
An example of how genetic background affects phenotype can be seen in horses. The Extension gene in horses is responsible for their coat color. A wild-type gene (EE) produces black pigment in the coat, while a mutant gene (ee) produces red pigment. A...

